Psychic grants access to Genesis Supernova, an insanely strong Psychic-type attack that proceeds to set up Psychic Terrain, protecting Mew from priority and boosting its Psychic afterwards. Fire Blast is the best coverage move because it hits common Pokemon in the tier such as Ferrothorn, Mega Scizor, Magearna, Mega Mawile, Tapu Bulu, and Celesteela. Nasty Plot and Rock Polish are run in the remaining two slots to wallbreak or attempt a late-game sweep. Focus Blast and Aura Sphere seem like appealing alternatives to Fire Blast, but Genesis Supernova already does a ton of damage to Heatran at +2 while Greninja has no reliable recovery. Hitting Tyranitar is often not worth dropping a setup move or the broader range of targets Fire Blast hits. Flamethrower also seems nice due to its perfect accuracy, but it misses the OHKO on Ferrothorn and specially defensive Mega Scizor.

Set Details
========

Mewnium Z gives Mew access to Genesis Supernova. A Timid nature allows Mew to win Speed ties against Mega Charizard Y and outpace Jolly Landorus-T, while a Modest nature gives Mew extra power, having a good chance to OHKO offensive Heatran after Stealth Rock damage and OHKO Mantine with Genesis Supernova, both after a Nasty Plot boost. Maximum Special Attack and Speed investment is used to hit as hard and be as fast as possible.

Usage Tips
========

Don't let Mew take damage for no reason, since this set has little defensive utility outside of checking Pokemon such as Mega Medicham in dire situations. Mew should bluff its more commonly used Will-O-Wisp set and take advantage of its initial switch-ins such as Clefable and Mega Diancie, as they either are complete setup bait or cannot prevent a second boost. Mew can also use Genesis Supernova without a boost to nuke or remove a threat. Even if the opponent has a Tyranitar, Mew can still use Genesis Supernova freely, since the chance of the opponent bringing Tyranitar on a possible Will-O-Wisp is very slim.

As said, this set is walled by Greninja, Tyranitar, and Mega Latias, so remove such threats before attempting to sweep. Finally, a well-timed Genesis Supernova sets up Psychic Terrain, which can protect faster teammates such as Mega Lopunny and Mega Diancie from priority attacks such as Water Shuriken, Quick Attack, and Bullet Punch.

Team Options
========

This set appreciates hazard removal, since an offensive set can be revealed when Leftovers recovery is not shown. Mega Scizor, Zapdos, and Tapu Fini are prime options, while Pokemon such as Latios, Excadrill, and Kartana can work on more offensive teams. Toxic Spikes absorbers such as Toxapex and Mega Venusaur are also appreciated. Spikes can be used on more offensive teams with Rapid Spin support from Excadrill, so Greninja is a solid teammate. Greninja can also pressure Tyranitar and some variants of Mega Latias. Tyranitar itself is also a solid teammate for Mew because it traps Mega Latias and discourages Choice Specs Greninja from spamming Dark Pulse. Offensive Mew surprises Clefable, so Pokemon that struggle with it are great team options. Mega Lopunny and Zygarde have a much easier time breaking the opponent's team with Clefable out of the way, for example. Switch-ins to the premier Dark-types in the tier, Greninja and Tyranitar, are required because Mew is bait to them. Ferrothorn, Tangrowth, and Landorus-T are solid options. Choice Scarf Keldeo can function as a solid offensive check to these threats and also struggles against Clefable, which Mew lures in.

Can be abrasive at times (no joke)

Looks solid overall, nothing really to add. I guess it might be worth mentioning somewhere how a well timed Genesis can potentially protect it from being revenge killed by common priority users such as Mega Mawile, Mega Sciz, Zygarde, etc.

It's ya boy GEEEEEEEEMARS

Flamethrower doesn't really miss the OHKO on Mega Scizor unless it's a spdef variant, even timid flamethrower has a 75% chance to ohko max hp mega scizor (68.8 if it's a 16 spdef variant) whereas timid fire blast only has a little bit more than a 50% chance to ohko most ferros after SR, and 25% after their leftovers recovery. just add in Specially Defensive before the mega scizor mention

a good point to mention of fire blast over flamethrower besides generally higher damage output and a chance to ohko ferro is that you can ohko TR magearna at +2 so it doesn't flip speed and bone you, and you're also able to ohko bisharp at +0 which is neat but i'll leave it up to your judgement as to whether or not that's worth a mention

i'd like to see flamethrower backslashed behind fire blast, but if you feel strongly that fire blast should be a solo move that's fine.

modest mew's +2 genesis supernova only has a ~>50% chance to ohko offensive tran after rocks, add in "having a good chance to OHKO" somewhere before the heatran line, something like "OHKOing Mantine and having a good chance to OHKO offensive Heatran after Stealth Rock, both after a Nasty Plot boost."

reorder the list of switch-ins to the premiere dark-types as "Ferrothorn, Tangrowth, and Landorus-T", lando-t shouldn't be mentioned first since it isn't a great switch in to greninja. consider adding scarf keldeo, since it's a decent offensive switch in to those dark-types and can struggle vs clefable

Psychic is Mew's main STAB move. It grants access to Genesis Supernova, an insanely strong Psychic-type attack that proceeds to set up the Psychic Terrain, protecting Mew from priority and boosting its Psychic afterwards. Fire Blast is the best coverage move because it hits common Pokemon in the tier such as Ferrothorn, Mega Scizor, Magearna, Mega Mawile, Tapu Bulu, and Celesteela. Nasty Plot and Rock Polish are ranrun in the remaining two slots to wallbreak or attempt a late-game sweep. Focus Blast or Aura Sphere seem like appealing alternatives to Fire Blast, but Genesis Supernova already does a ton of damage to Heatran at +2 while Greninja has no reliable recovery. Hitting Tyranitar is often not worth dropping a setup (RH) move or the broader range of targets Fire Blast hits. Flamethrower also seems nice due to its perfect accuracy, but it misses the OHKO on Ferrothorn and specially defensive Mega Scizor.

Set Details
========

Mewnium Z is the item of choice since it gives Mew access to Genesis Supernova. A Timid nature allows Mew to win Speed ties against Mega Charizard Y and outpace Jolly Landorus-T, while a Modest nature gives Mew extra power, having a good chance to OHKO offensive Heatran after Stealth Rock damage[optional, sounds a bit better w/ the flow here imo] and OHKO Mantine with Genesis Supernova, both after a Nasty Plot boost. Maximum Special Attack and Speed investment is used to hit as hard and be as fast as possible.

Usage Tips
========

Don't let Mew take damage for no reason, since this set has little defensive utility outside of checking Pokemon such as Mega Medicham in dire situations. Mew should bluff its more commonly used Will-O-Wisp set and take advantage of its initial switch-ins such as Clefable and Mega Diancie, as they are either complete setup (RH) bait or cannot prevent a second boost. Mew can also use Genesis Supernova without a boost to nuke or remove a threat. Even if the opponent has a Tyranitar, Mew can still use Genesis Supernova freely, since the chance of the opponent bringing Tyranitar on a possible Will-O-Wisp is very slim.

As said, this set is walled by Greninja, Tyranitar, and Mega Latias, so remove such threats before attempting to sweep. Finally, a well-timed Genesis Supernova sets up Psychic Terrain, (AC) which can protect faster teammates such as Mega Lopunny and Mega Diancie from priority attacks such as Water Shuriken, Quick Attack, and Bullet Punch.

Team Options
========

This set appreciates hazard removal, since an offensive set can be revealed when Leftovers recovery is not shown. Mega Scizor, Zapdos, and Tapu Fini are prime options, while Pokemon such as Latios, Excadrill, and Kartana can work on more offensive teams. Toxic Spikes absorbers such as Toxapex and Mega Venusaur are also appreciated. Spikes can be used on more offensive teams with Rapid Spin support from Excadrill, [optional clarification] so Greninja is a solid teammate. ItGreninja[clarifying between greninja and spikes] can also pressure Tyranitar and some variants of Mega Latias. Tyranitar itself is also a solid teammate for Mew because it traps Mega Latias and discourages Choice Specs Greninja from spamming Dark Pulse. Offensive Mew surprises Clefable, so Pokemon that struggle with it are great team options. Mega Lopunny and Zygarde have a much easier time breaking the opponent's team with Clefable out of the way, (AC) for example. Switch-ins to the premier Dark-types in the tier, Greninja and Tyranitar, are required because Mew is bait to them. Ferrothorn, Tangrowth, and Landorus-T are solid options. Choice Scarf Keldeo can function as a solid offensive check to these threats and it also struggles against Clefable, (AC) which Mew lures in.

Psychic grants access to Genesis Supernova, an insanely strong Psychic-type attack that proceeds to set up Psychic Terrain, protecting Mew from priority and boosting its Psychic afterwards. Fire Blast is the best coverage move because it hits common Pokemon in the tier such as Ferrothorn, Mega Scizor, Magearna, Mega Mawile, Tapu Bulu, and Celesteela. Nasty Plot and Rock Polish are run in the remaining two slots to wallbreak or attempt a late-game sweep. Focus Blast orandAura Sphere seem like appealing alternatives to Fire Blast, but Genesis Supernova already does a ton of damage to Heatran at +2 while Greninja has no reliable recovery. Hitting Tyranitar is often not worth dropping a setup move or the broader range of targets Fire Blast hits. Flamethrower also seems nice due to its perfect accuracy, but it misses the OHKO on Ferrothorn and specially defensive Mega Scizor.

Set Details
========

Mewnium Z is the item of choice since it gives Mew access to Genesis Supernova. A Timid nature allows Mew to win Speed ties against Mega Charizard Y and outpace Jolly Landorus-T, while a Modest nature gives Mew extra power, having a good chance to OHKO offensive Heatran after Stealth Rock damage and OHKO Mantine with Genesis Supernova, both after a Nasty Plot boost. Maximum Special Attack and Speed investment is used to hit as hard and be as fast as possible.

Usage Tips
========

Don't let Mew take damage for no reason, since this set has little defensive utility outside of checking Pokemon such as Mega Medicham in dire situations. Mew should bluff its more commonly used Will-O-Wisp set and take advantage of its initial switch-ins such as Clefable and Mega Diancie, as they are either are complete setup bait or cannot prevent a second boost. Mew can also use Genesis Supernova without a boost to nuke or remove a threat. Even if the opponent has a Tyranitar, Mew can still use Genesis Supernova freely, since the chance of the opponent bringing Tyranitar on a possible Will-O-Wisp is very slim.

As said, this set is walled by Greninja, Tyranitar, and Mega Latias, so remove such threats before attempting to sweep. Finally, a well-timed Genesis Supernova sets up Psychic Terrain, which can protect faster teammates such as Mega Lopunny and Mega Diancie from priority attacks such as Water Shuriken, Quick Attack, and Bullet Punch.

Team Options
========

This set appreciates hazard removal, since an offensive set can be revealed when Leftovers recovery is not shown. Mega Scizor, Zapdos, and Tapu Fini are prime options, while Pokemon such as Latios, Excadrill, and Kartana can work on more offensive teams. Toxic Spikes absorbers such as Toxapex and Mega Venusaur are also appreciated. Spikes can be used on more offensive teams with Rapid Spin support from Excadrill, so Greninja is a solid teammate. Greninja can also pressure Tyranitar and some variants of Mega Latias. Tyranitar itself is also a solid teammate for Mew because it traps Mega Latias and discourages Choice Specs Greninja from spamming Dark Pulse. Offensive Mew surprises Clefable, so Pokemon that struggle with it are great team options. Mega Lopunny and Zygarde have a much easier time breaking the opponent's team with Clefable out of the way, for example. Switch-ins to the premier Dark-types in the tier, Greninja and Tyranitar, are required because Mew is bait to them. Ferrothorn, Tangrowth, and Landorus-T are solid options. Choice Scarf Keldeo can function as a solid offensive check to these threats and it also struggles against Clefable, which Mew lures in.